It's really unlikely that most people will gain a lot of money from these kinds of installations nowadays (an EV probably tips that somewhat). The big benefit

It's really unlikely that most people will gain a lot of money from these kinds of installations nowadays (an EV probably tips that somewhat). The big benefit is the resilience. Since you are using them every day, they will be far more likely to work in the event of an outage than a gasoline generator that you test once a year.